THERMAL SPRAY COATING

Thermal spraying is a group of processes wherein a feedstock material is head and propeeled as individual particles or droplets onto a surface. The thermasl spray gun generates the necessary heat by combustible gases or an electric art. As the materials are haeted, they are change to a plstic or molten sate and are confined and accelerated by a compressed gas straem to the substrate.

It is one of the most versatile hard facing techniques available for the application of coating materials used to protect component from abrasive wear, adhesive wear, erosive wear or surface fatigue and corrosion (such as that caused by oxidation or seawater). The coating may also increase heat resistance, when a material with a low thermal conductivity is deposited onto a base material. A variety of enginnering problems have been solved using thermal spraying application of this coating technique considered. Metals, carbides and cerments are the most widely used coating materials, however the spraying of polymers has been researched also. Within the thermal spray technique are various types of processes, one of which is the High Velocity Oxy-Fuel (HVOF) process used in the current reseach. The HVOF processes in one of the most popular thermal spraying technologies and has been widely adopted by many industries due to it is flexibility and the superior quality of coating produced. The HVOF processe is a relatively new thermal spray process, offering coating with higher bond strenght and hardness together with lower porosity, compared to it is other thermal spray counterpart. Industrial use of the process is growing according to especially in the power generation industry, oil and gas, seel mill and aeronautical industry